Novel Tumor-Specific Antigens for Immunotherapy Identified From Multi-omics Profiling in Thymic Carcinomas

Thymic carcinoma (TC) is the most aggressive thymic epithelial neoplasm. TC patients with microsatellite instability, whole-genome doubling, or alternative tumor-specific antigens from gene fusion are most likely to benefit from immunotherapies. However, due to the rarity of this disease, how to prioritize the putative biomarkers and what constitutes an optimal treatment regimen remains largely unknown. Therefore, we integrated genomic and transcriptomic analyses from TC patients and revealed that frameshift indels in KMT2C and CYLD frequently produce neoantigens. Moreover, a median of 3 fusion-derived neoantigens was predicted across affected patients, especially the CATSPERB-TC2N neoantigens that were recurrently predicted in TC patients. Lastly, potentially actionable alterations with early levels of evidence were uncovered and could be used for designing clinical trials. In summary, this study shed light on our understanding of tumorigenesis and presented new avenues for molecular characterization and immunotherapy in TC.

Polarising Frantz Tumors – Benign And Malignant Solid Pseudopapillary Epithelial Neoplasm Of Pancreas – Twin Case Reports

Solid pseudo-papillary epithelial neoplasm (SPEN), also known Hamoudi tumors or Franz tumors, are rare pancreatic neoplasm which are almost always seen in young women predominately of non-Caucasian descent with only a small minority of cases diagnosed in men [1]. The first published description of an SPN was by Frantz in 1959[2]. . It is a rare tumor comprising of less than 3 percent of all pancreatic tumor. It is seen most often in the region of tail of pancreas. This tumor is mostly asymptomatic and usually detected when it reaches large size. These are tumors with low malignant potential and rarely vascular invasion and metastatic disease can be seen in aggressive cases. Here we report two cases, one each of benign SPEN and malignant SPEN with contrasting imaging findings and polar outcomes.

Gastric epithelial neoplasm of fundic-gland mucosa lineage: proposal for a new classification in association with gastric adenocarcinoma of fundic-gland type

Background Gastric adenocarcinoma of fundic-gland type (GA-FG) is a rare variant of gastric neoplasia. However, the etiology, classification, and clinicopathological features of gastric epithelial neoplasm of fundic-gland mucosa lineage (GEN-FGML; generic term of GA-FG related neoplasm) are not fully elucidated. We performed a large, multicenter, retrospective study to establish a new classification and clarify the clinicopathological features of GEN-FGML. Methods One hundred GEN-FGML lesions in 94 patients were collected from 35 institutions between 2008 and 2019. We designed a new histopathological classification of GEN-FGML using immunohistochemical analysis and analyzed via clinicopathological, immunohistochemical, and genetic evaluation. Results GEN-FGML was classified into 3 major types; oxyntic gland adenoma (OGA), GA-FG, and gastric adenocarcinoma of fundic-gland mucosa type (GA-FGM). In addition, GA-FGM was classified into 3 subtypes; Type 1 (organized with exposure type), Type 2 (disorganized with exposure type), and Type 3 (disorganized with non-exposure type). OGA and GA-FG demonstrated low-grade epithelial neoplasm, and GA-FGM should be categorized as an aggressive variant of GEN-FGML that demonstrated high-grade epithelial neoplasm (Type 2 > 1, 3). The frequent presence of GNAS mutation was a characteristic genetic feature of GEN-FGML (7/34, 20.6%; OGA 1/3, 33.3%; GA-FG 3/24, 12.5%; GA-FGM 3/7, 42.9%) in mutation analysis using next-generation sequencing. Conclusions We have established a new histopathological classification of GEN-FGML and propose a new lineage of gastric epithelial neoplasm that harbors recurrent GNAS mutation. This classification will be useful to estimate the malignant potential of GEN-FGML and establish an appropriate standard therapeutic approach.

Solid pseudopapillary epithelial neoplasia of the pancreas causing sinistral portal hypertension: a case report

Solid pseudopapillary epithelial neoplasm (SPEN), also referred as Franz’s tumour or Hamoudi’s tumour is a low malignant potential epithelial neoplasm of the pancreas. It occurs at a much lower frequency than other cystic neoplasms of the pancreas. It occurs rarely and in young females. Although infrequently, large sized tumours are known to compress the splenic vein thereby resulting in extra hepatic portal venous obstruction (EHPVO) resulting in left sided portal hypertension (PHT). The resulting periportal collateral circulation poses an intraoperative challenge while approaching these tumors. Meticulous pre-operative planning can go a long way in managing such a case and providing complete surgical cure. We present a case of SPEN in a 37 years old female which was discovered incidentally and managed surgically to achieve a complete cure to both the tumour and the left sided PHT.

Incidentally detected renal oncocytoma treated with nephrectomy in a surgical unit of a district general hospital.

Renal oncocytoma is a benign renal epithelial neoplasm. In this case report we present a case of incidentally detected renal oncocytoma which was treated with nephrectomy.

The Accuracy of Intraoperative Frozen Sections in Epithelial Ovarian Tumor

Objective: To evaluate the accuracy of the intraoperative frozen section in the diagnosis of epithelial ovarian tumor. Materials and Methods: An observational study of epithelial ovarian tumor reports from patients that underwent surgery with intraoperative consultation at Ramathibodi Hospital, Thailand between 2013 and 2017 was done. The frozen section diagnoses were compared with the final surgical diagnoses and the overall accuracy, sensitivity, specificity, positive predictive values (PPV), negative predictive values (NPV) were studied. Results: One hundred sixteen ovarian specimen reports were reviewed, comprised of 74 (63.8%) benign, 21 (18.1%) borderline, and 21 (18.1%) malignant neoplasms. Nine cases (7.7%) were discordant diagnoses. The overall accuracy was 92.2%. The sensitivity and specificity for benign, borderline, and malignant neoplasms were 100%, 80.9%, and 76.2%, and 88.1%, 95.8%, and 100%, respectively. The PPV and NPV for benign, borderline, and malignant neoplasms were 93.7%, 80.9%, and 100%, and 100%, 95.8%, and 95.0%, respectively. Conclusion: The intraoperative frozen section has high accuracy in the diagnosis of ovarian epithelial neoplasm. The results can be used in guidance on the extent and type of surgical management. Keywords: Frozen section, Accuracy, Epithelial ovarian tumor

Pathohistological and Immunohistochemical Analysis, Differential Diagnosis, Prognosis and Complex Treatment in a Rare Lymphoepithelioma-Like Breast Cancer

We present a 78-year-old woman with a rare neoplasm of the right mammary gland – Lymphoepithelioma-like carcinoma (LELC). Lymphoepithelioma-like carcinoma is an undifferentiated neoplasm, consisting of malignant epithelial cells on the background of lymphocytes. Pathomorphological features and immunohistochemical (IHC) analysis determines the rare pathohistological variant of breast cancer. This clinical case of lymphoepithelioma-like breast cancer is the 34th published in medical literature in English. In the discussion, we emphasize the importance of immunohistochemical analysis to assess the differential diagnosis with other benign and malignant breast tumors . Lymphoepithelioma-like breast cancer is an extremely malignant epithelial neoplasm with an unfavorable prognosis, requiring complex oncological treatment.

Mixed Large Cell Neuroendocrine Carcinoma of the Ovary: Report of a Rare Case

LCNC (large cell neuroendocrine carcinomas) of the ovary is a rare aggressive tumor entity of the genital tract. Its pathogenesis, origin, and prognosis have not been fully elucidated, since there are a limited number of cases reported in literature. We report a case of an 80-year-old patient, who presented with a growing abdominal mass, which turned out to be a mixed LCNC/epithelial neoplasm. Although this type of tumor is rare, the continuous development of pathologoanatomy and immunohistochemistry contributes to our better knowledge and comprehension of these neoplasms.